Pyrolytic conversion of oil shale



Sept. 2, 1952 K. CHENEY 2,609,331

PYROLYTIC CONVERSION OF OIL SHALE Filed June 17, 1947 SHALE 2 8 I WATER 4 (PM CATALYST RIND R I 6 G E MIXER FILTER soLuT|oT| i CONDENSER INVENTOR. PROD'UCT 52 LEROY K. CHENEY ATTORNEYS Patented Sept. 2, 1952 ,PYROWTIQ 'QONVBBSION'OF OIL SHALE Lemy i -i ignor -t Sin-.

lair Refining- Compa corporation of Maine Application June-l'l, 1947, Serial No; 755,231

"3 Claims rf, (01. 202511) recpvery'of oil from oil-bearing shale andmore particularly to the process of producing shale oil from oil-bearingshales by the thermal pyrolysis thereof in thepresence of a catalyst which favors thedisintegration of the shale and the produc t dn ofto 'l the e m any proposals e be n a ove a long riod i a s f r he ec v ry' 5 I m O l? erzinsshales t a of on m c so s.

mer can s ales ave t be n w ked one c memercialscale, As long as the price of petr leum oil was lowenough and it was sufliciently ,plenti: fill, it. was impracticable to produce shale oil in competition."Howeverfthe natural resources of petroleum are beingfused up at an enormous rate .and costs of petroleum" production are increasinge- Tlierecovery of-oil fromoil shale therefore becomes more practical and necessary An important feature .ofilmyl invention relates to the retorting of oil shale in the presence of catalysts which permit the used lower retorting',

temperature and "produce improved shale oil:

apparatus which the, steps of my, improved process may be carried out.

The 011 shale to be processed, in an advantageous form of my invention, is introduced into the apparatus from a suitable supply through a chute or conduit 2, provided with a rotary feed valve 4, into a crusher or grinder B which may be of any suitable type, the grinding elements of which may be operated by a drive-wheel 8. The process maybe operated in a continuous manner or in batch or in semi-batch procedure, but is illustrated by the grinding of a suitable quantity of shale in the grinder 6 in the presence of water introduced through a valved line l0 so as to produce a slurry. During the final stages of grinding of the slurry, a catalytic acid such as hydrofluoric acid or hydrochloric acid, is introduced into the grinder 6 through a line l2, and intimately mixed and ground with the slurry. The proportion of 136 where the catalyzed oil; shale. is: retortedvat. a:

acid to oil shale may vary'from-0. 5-1to '6% of---the-: dry shale by weight, depending upon the pH- ofh theslurry and the acid llS6d;- I a The other-parts of the apparatus shownbelow the grind'er 6 includesa mixer Hand-a filter a 16. I The mixture of-slurry and catalyst produced in the grinder- 6 ispreferably conducted thro l a conduit 20, having a rotary feed valveor'othe typetof valve therein so that the completion of themixing operation .is 'efiected in =the'mixe'r' H 411 whichrmay be'operated, for example, bya c lrivewheell22. A new batch may then 'bestarted in the grinder 6. a v

After the mixing is completed the oil-shale andicatalyst or activated. slurryrform' is conducted through a conduit24, having a rotary-feedvalve or other.- type ofv valve therein; into the filter -l6. Any, solution removed. by the filter iswithdrawn therefrom througha. valved line. "26, and thereaftersthe. filter cake, which .of courseis Stl11 Wetfl- -is dried and therefore preferably conveyed direct- 1y into a dryer..28 from theifilter l6, as fortex ample, througha chute, 'conveyonor. conduit,= il-:-:. lustrated by the conduit 3.0,. having a rotary feed valve or other type valve therein. Inrtheiopera tion :described, the wet' catalytioally. active oil. shaleis dried in any suitable manner in the dryer 28, the'moisture-laden air produced by the dry-vi. ing being withdrawn through a flue 32. Thedryer flfl may. be. of any conventional form, as forexample, a continuous Joeltor chainzdryerli. provided with means forsupplyingzheatandsair-i; for. drying purposes. The driedecatalyst andfinelya ground .oil shale is transferred-from thedryeri 285.;

through a sealing rotary feedvalvte 34; into. a retort;

suitable temperature,of from 850 F. to 1:1 LOOPJR; for the productionand recovery of oil fromatheca shale. The spent shale is discharged from the retort through a chute 38 provided with a sealing rotary feed valve, as indicated.

The oil vapors produced in the retorting operation are conducted through a vapor line 40 into a fractionating tower 42 in which the higher boiling constituents of the oil, as for example, that boiling above the gasoline range, is condensed, the resulting condensed product being withdrawn through a valved line 44. The gases and gasoline constituents produced in the retorting operation are conducted overhead from the tower 42 through a vapor line 46 and subjected to cooling and condensation in a condenser 48. The condensate and gases are withdrawn through a valved line 50 to a suitable gas separator and condensate receiver (not shown) The retort 36 may be of any conventional type in which .meansis provided for removing vapors at points adjacent their formation. Theretort 36, as shown, may be provided with a conveyor means by which the oil shale is slowly moved through the retort while it is being heated to,

produce the shale oil.

The acid used in the pretreatment of the shale during the grinding and mixing operations, reacts with the inorganic constituents in the shale, such as the silicon, aluminum and iron vcompounds to produce active catalysts which greatly facilitate the production of the oil from the shale with a minimum of carbon production, and at the same time produce a shale oil product which has a higher API gravity than .would otherwise be produced. During the retorting operation under catalytic conditions, the oil at the instant it is produced from the shale also comes under the influence of the catalyst at the high temperatures necessary, and is to a considerable extent, con-- vertecl. to products of lower API gravity so that in a retorting' operation as described, a consideraluminum fluoride, or mixed aluminum chlorides and fluoride, orcomplex aluminum fluorochlorides. Any known oil cracking catalyst may be used in my process in addition to those mentioned above, and mixtures of catalysts may be employed, as for example, hydrogen fluoride or hydrochloric acid may be used along with the Acid mixed with the I catalyst salts or oxides. catalyst slurry in the grinder 6 and mixer 14 is adsorbedinto the oil shale to produce complex catalytic materials with the constituents of the shale.

I claim:

1. In the process of producing shale oil from oilshale, including the retorting of the oil shale, the improvement which comprises grinding the oil-shale to be processed with water to form a slurry, treating the slurry with a material selected from the group consisting of hydrochloric acid, hydrofluoric acid, and hydrogen fluoride in an amount equal to 0.5 to 6% by weight of the oil shale in the slurry whilethoroughly mixing 4 said material with the slurry thereby catalytically activating inorganic constituents of the oil shale. filtering the slurry to remove excess water, drying the filtered oil shale, and subjecting it to a retorting operation and producing shale oil therefrom.

2. In the-process of producing shale foil from oil shale,"including the retorting' ofth oil shale, the improvement which comprises grinding the oil shale to be processed with water to form a I slurry, treating the slurry with hydrofluoric acid in an amount equal to 0.5 to 6% by weight of the oil shale in the slurry while thoroughly mixing saidmaterial with the slurry thereby producing a fluoride catalyst for catalyzing the shale oil production in the retorting operation, filtering the slurry to remove excess water, dryin the filtered oil shale, and subjecting it to a retorting operation and producing shale oil therefrom.

3. In the process of producing shale oil from oil shale, including the retorting of the oil shale, the improvement which comprises grinding the oil shale to be processed with water to form a slurry, treating the slurry with hydrogen fluoride in an amount equal to 0.5 to 6% by weight of the oil shale in the slurry while thoroughly mixing said material with the slurry thereby producing a fluoride catalyst for catalyzing the shaleoil production in the retorting operation, filtering the slurry to remove excess Water, drying thfil tered oil shale, and subjecting it to a'retorting operation and producing shale oiltherefrom.

' LEROY K; CHENEY.

REFERENCES CITED The following references are of record the;

file of this patent; V

UNITED STATES PATENTS Number Name Date, 1,276,879, Crane Aug. 27, 1918' 1,280,178 Day' Oct. 1,1918 1,510,983 Dolbear Oct. 7, 1924' 1,773,839 Zieley et a1. Aug. 26, 1930 1,941,809 McKee Jan. 2, 1934 2,431,677 Brown Dec. 2, 1947 FOREIGN PATENTS Number Country Date 290,696 Great Britain Apr. 25, 1929 394,639 Great Britain Sept. 21, 1931 19,231 Australia Sept. 5, 1935 of 1934 OTHER REFERENCES Bureau of Mines Information Circular 7481', October 1948, pages Mo 11 and Figure 3. 

1. IN THE PROCESS OF PRODUCTING SHALE OIL FROM OIL SHALE, INCLUDING THE RETORTING OF THE OIL SHALE, THE IMPROVEMENT WHICH COMPRISES GRINDING THE OIL SHALE TO BE PROCESSED WITH WATER TO FORM A SLURRY, TREATING THE SLURRY WITH A MATERIAL SELECTED FROM THE GROUP CONSISTING OF HYDROCHLORIC ACID, HYDROFLUORIC ACID, AND HYDROGEN FLUORIDE IN AN AMOUNT EQUAL TO 0.5 TO 6% BY WEIGHT OF THE OIL SHALE IN THE SLURRY WHILE THOROUGHLY MIXING SAID MATERIAL INORGANIC CONSTITUENTS OF THE OIL SHALE, ACTIVATING INORGANIC CONSTITUENTS OF THE OIL SHALE, FILTERING THE SLURRY TO REMOVE EXCESS WATER, DRYING THE FILTERED OIL SHALE, AND SUBJECTING IT TO A RETORTING OPERATION AND PRODUCING SHALE OIL THEREFROM. 